<%@ page language="java" contentType="text/html; charset=UTF-8" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Insert title here</title>
</head>
<body>
<%
	// 如果用户名已经存在，说明已经登录，跳转到主页
	String username = (String) request.getSession().getAttribute("username");
	if (username != null && username.length() > 0) {
		response.sendRedirect("index.jsp");
		return;
	}
%>
<form action="<%=request.getContextPath()%>/servlet/LoginServlet" method="post">
用户：<input type="text" name="username" />
密码: <input type="password" name="password" />
昵称: <input type="text" name="nickname" />
<input type="submit" value="登录" /><br>
</form>
</body>
</html>